MR Imaging Differentiation of Soft-Tissue Hemangiomas from Malignant Soft-Tissue Masses

Abstract

OBJECTIVE: The purpose of this study was to determine whether MR imaging features can reliably distinguish hemangiomas from malignant soft-tissue masses. MATERIALS AND METHODS: We retrospectively reviewed MR imaging studies of 22 patients with soft-tissue hemangiomas and 22 patients with malignant soft-tissue masses. Images were reviewed and agreement reached by a consensus interpretation of two observers and by an independent observer. Masses were evaluated for signal intensity on T1- and T2-weighted images, for enhancement with gadolinium administration, and for morphology (lobulation, septation, central low-intensity dots). Lesion T2 signal and lesion enhancement with gadolinium administration were also objectively measured using regions of interest and comparison with skeletal muscle. RESULTS: Signal intensity on T1-weighted imaging of hemangiomas and malignant soft-tissue masses was similar. Subjective analysis showed greater T2 signal and gadolinium enhancement in hemangiomas; however, the differences were not statistically significant on objective analysis. Lobulation, septation, and central low-signal-intensity dots were all more common in hemangiomas, with statistical significance achieved; the combination of all three findings was specific for hemangioma. CONCLUSION: Although no single MR imaging feature was diagnostic in this study, analysis of lesion morphology, signal intensity, and enhancement with gadolinium allowed MR imaging differentiation of hemangiomas from malignant soft-tissue masses.